Yoyi DHG-9246A Vertical Forced-Air Constant-Temperature Drying Oven

Overview

The Yoyi DHG-9246A is a vertically oriented, forced-air constant-temperature drying oven engineered for precision thermal processing in regulated laboratory and industrial quality control environments. It operates on the principle of convective heat transfer via a rear-mounted, adjustable air circulation system—designed to ensure uniform temperature distribution across the full 225 L stainless-steel chamber. Unlike natural convection ovens, this model employs an integrated blower and optimized wind-path architecture to achieve ≤±2.5% temperature uniformity (measured at 100°C, empty chamber), meeting the performance requirements specified in GB/T 30435–2013 for electrically heated forced-air drying equipment. Its operational range spans from ambient +10°C to 300°C, making it suitable for applications including moisture loss determination, polymer curing, pre-sterilization drying of glassware, thermal aging of electronic components, and residual solvent removal in pharmaceutical intermediates.

Key Features

• Microprocessor-based PID temperature controller with 0.1°C resolution, real-time display of setpoint, actual chamber temperature, and remaining hold time—all visible on a single-line LCD menu interface.
• Mirror-finish SUS304 stainless-steel interior chamber with three adjustable, load-bearing stainless steel shelves; corrosion-resistant and compliant with GLP cleaning validation protocols.
• Dual-layer tempered glass observation window with silicone gasket seal, enabling non-intrusive visual monitoring without compromising thermal integrity or operator safety.
• Robust cold-rolled steel outer casing with electrostatic epoxy-polyester powder coating for long-term resistance to abrasion, chemical splashes, and environmental oxidation.
• High-efficiency rear-mounted air duct system featuring automatic intake/exhaust venting—eliminates manual damper adjustment and actively manages internal humidity during extended drying cycles.
• Independent over-temperature cut-off circuit (optional) compliant with IEC 61000-4-2 immunity standards, interrupting power when user-defined safety thresholds are exceeded.
• Power-fail recovery function: automatically restores previously configured parameters—including setpoint, timer status, and ramp/soak profiles—upon re-energization.

Sample Compatibility & Compliance

The DHG-9246A accommodates a broad spectrum of sample formats—from Petri dishes and weighing boats to standard ISO trays (up to 500 × 600 mm footprint) and stacked component racks. Its chamber geometry supports both batch and sequential processing of biological media plates, ceramic substrates, metal coupons, and polymeric films. The unit conforms to GB/T 30435–2013 for metrological performance, electrical safety (GB 4793.1), and electromagnetic compatibility (GB/T 18268.1). While not certified to UL or CE for export markets, its design principles align with ASTM E145–22 (Standard Specification for Gravity-Convection and Forced-Ventilation Ovens) and supports traceable calibration per ISO/IEC 17025 requirements when paired with NIST-traceable reference thermometers.

Software & Data Management

The base configuration includes RS485 serial communication capability (Modbus RTU protocol), enabling integration into centralized lab management systems for remote parameter setting, real-time temperature logging, and alarm event capture. Optional accessories include an embedded thermal printer (supporting timestamped printouts of temperature profiles) and PC-based software for generating 21 CFR Part 11–compliant audit trails—including user login history, parameter change logs, and electronic signatures. All data outputs are CSV-compatible and support post-processing in MATLAB, Python (Pandas), or LIMS platforms. Firmware supports up to 99 programmable segments for multi-step thermal profiles (e.g., ramp-hold-cool sequences), with slope limiting to prevent thermal shock in sensitive materials.

Applications

• Moisture content analysis in foodstuffs, grains, and feedstuffs per AOAC 950.46 and ISO 665.
• Drying and conditioning of filter papers, crucibles, and volumetric glassware prior to gravimetric analysis.
• Thermal stabilization of reference standards used in analytical chemistry (e.g., KHP, NaCl) under controlled humidity-free conditions.
• Curing of epoxy-coated PCBs and conformal coatings in electronics manufacturing QA labs.
• Pre-treatment of soil and sediment samples prior to heavy-metal extraction (EPA Method 3050B).
• Accelerated aging studies of elastomers and thermoplastics per ASTM D573 and ISO 188.
• Inert-atmosphere drying via optional nitrogen purge port (fitted with calibrated rotameter), supporting oxygen-sensitive catalysts and lithium battery electrode materials.

FAQ

What is the maximum operating temperature and how is thermal stability verified?
The DHG-9246A achieves a maximum setpoint of 300°C with ±1.0°C fluctuation (measured over 30 min at steady state, per GB/T 30435–2013 Annex B). Stability is validated using calibrated Class A Pt100 probes placed at nine standardized chamber locations.
Can the oven be validated for GMP-compliant processes?
Yes—when equipped with optional multi-point data loggers and 21 CFR Part 11 software, it supports IQ/OQ/PQ documentation packages. Calibration certificates traceable to CNAS-accredited laboratories are available upon request.
Is the stainless-steel chamber electropolished or passivated?
The interior uses mirror-finish 304 stainless steel (Ra ≤ 0.8 µm); electropolishing and citric acid passivation services can be arranged as a value-added option.
Does the unit support ramp-and-soak programming out of the box?
No—multi-segment programming requires the optional multi-stage temperature controller (part #DHG-PROG-9X), sold separately.
What maintenance intervals are recommended for the blower motor and heating elements?
Blower bearings require lubrication every 12 months; heating element resistance should be verified quarterly. Full preventive maintenance kits—including replacement gaskets, fuses, and thermal fuses—are available under part #DHG-PM-KIT-9246A.